In article ,
"David Hare-Scott" wrote:

Billy wrote:
In article ,
"David Hare-Scott" wrote:

andy candy wrote:
This year I decided to try growing some fennel in my garden.
Unbeknownst to me, however, fennel apparently inhibits the growth of
tomatoes -- at least this is what I have been told. Can anyone
testify personally to this? Should I also uproot the fennel once
it's big enough? I have it growing on both ends of my garden, right
next to my Brandywine and Caspian Pink plants. Alternately, is
there a "safe" distance away from my tomatoes where I can
transplant the fennel? I'm also curious if anyone knows how the
inhibitive fennel effect works -- via the roots, flowers, fully
grown plants, whatever.

Much obliged to all for any shared advice.

Drew (rhymes with Grew)

I have grown fennel in many parts of my garden for years, it now
self-seeds all over and I pull out the ones I don't need. I have
not noticed it inhibiting anything.

David

Thanks for the reality check, David. Is this the type of fennel that
grows a bulb or the one that grows a large tap root?

The bulb sort 'Florence' fennel, I have no idea if that is important.
Apparently there is evidence of some allelopathy from some sort of fennel
but in the studies I saw it doesn't affect all plants and some proven
effects are not very strong.

David

Thanks for growing my vocabulary and my consciousness.

http://everything2.com/title/allelopathy

A good example of an allelopathic species is production of inhibitory
chemicals by fennel. The roots of fennel plants produce a suite of
chemicals which can reduce the root elongation, root hair growth and
germination of neighbouring plants, like lettuce. This is an example of
allelopathic exudation.
---

A good example maybe, but from your observations, DAvid, not persuasive.
The wild fennel in my garden, has always been off by itself and doesn't
try to spread, so I've never seen any interaction. Something to keep an
eye out for.
--

- Billy
"For the first time in the history of the world, every human being
is now subjected to contact with dangerous chemicals, from the
moment of conception until death." - Rachel Carson

http://www.youtube.com/watch?v=En2TzBE0lp4

http://www.haaretz.com/hasen/spages/1050688.html